Installation Of 7W4426 Tachometer Conversion Kit{7462} Caterpillar

D330C, 3304 (2B, 4B, 5B);
D333C, 3306 (9A, 23C, 66D, 67D, 70R);
D334 (92B, 93B);
D336 (55B, 60B);
D342, D342C (5A, 31B, 32B, 49B, 50B);
D343A (33B, 62B);
D346 (39J, 40J);
D348 (36J, 38J);
D349 (61P, 62P);
D353C, D353D, D353E (46B, 47B);
D379A, D379B (68B, 69B);
D398A, D398B (66B, 67B);
D399 (35B, 91B);
G333C (68D);
G342C (71B);
G343 (97N);
G353D (64B);
G379A (72B);
G398A (73B);
G399 (49C)

The 7W4426 Tachometer Conversion Kit is the parts service replacement for 4L1706 Tachometer, 3N7615 Transmitter and 3L6649 Power Unit. The new digital tachometer eliminates the need for a battery operated power unit. To install the kit, see the instructions that follow.

(1) Remove tachometer (1), transmitter assembly (2), power unit (3) and the wiring.

(2) Remove bracket (4) from 7T4677 Tachometer (5). Fasten 7W3080 Adapter (6) on tachometer (5) with bracket (4). Tighten nuts (7) to a maximum torque of 0.9 N·m (8.0 lb in). Put the tachometer assembly in the opening left by the former tachometer. Drill three holes (A) through adapter (6) and the panel. Fasten adapter (6) to the panel with self-tapping screws.

(3) Install 7T8275 Shaft (8) in 7T6945 Generator (9). Install the generator and shaft on the tachometer drive [located at the fuel pump/governor area].

(4) Use enough 6V2744 Wire (10) to connect generator (9) to tachometer (5). Strip the ends of the wires on one end of wire (10) and install two 9G3186 Terminals (11). Cut the ground wire even with the shielding. On the other end of wire (10), strip the wires and fasten two 7N7221 Terminals (12) and a 5P5592 Terminal (13) as shown. Fasten terminals (11) to the tachometer and terminals (12) to the generator. Connect terminal (13) to the engine block. See Wiring Diagram on page 4 for the application needed.

Wiring Diagram

WIRING DIAGRAM WITH ELECTRIC GOVERNOR AND WITHOUT DUAL SPEED SWITCH

WIRING DIAGRAM WITH DUAL SPEED SWITCH

WIRING DIAGRAM FOR TACHOMETER CIRCUIT ONLY

A Magnetic Pick-up

B Tachometer

C Governor Control Terminal Strip

D Dual Speed Switch Terminal Strip

E Terminal Connections - Terminals 18 and 19 on load sharing governor control and terminals 7 & 8 on stand-by governor control.

F Wiring Connections - For second tachometer circuit if needed.

G Ground Connection - Ground to engine.

H Ground Connection - Governor control chassis ground.

J All Wire Must Be 22AWG Shielded Cable Or Larger.